U.S. patent application number 15/092051 was filed with the patent office on 2016-08-04 for polarizing plate and image display device.
This patent application is currently assigned to FUJIFILM Corporation. The applicant listed for this patent is FUJIFILM Corporation. Invention is credited to Makoto ISHIGURO.
Application Number | 20160223719 15/092051 |
Document ID | / |
Family ID | 52813174 |
Filed Date | 2016-08-04 |
United States Patent
Application |
20160223719 |
Kind Code |
A1 |
ISHIGURO; Makoto |
August 4, 2016 |
POLARIZING PLATE AND IMAGE DISPLAY DEVICE
Abstract
Provided are a polarizing plate having excellent surface
hardness and excellent adhesiveness between a polarizer and a resin
layer arranged on the polarizer, and an image display device
including the polarizing plate. The polarizing plate of the present
invention includes a polarizer and a resin layer directly in
contact with the polarizer, the resin layer is a layer obtained by
polymerizing and curing a boronic acid monomer having a boronic
acid group denoted by Formula (1) and a polymerizable group, and a
multifunctional monomer, Re(550) and Rth(550) of the resin layer
respectively satisfy Expression (X) and Expression (Y) described
below, and the thickness of the polarizer is less than or equal to
35 .mu.m. Expression (X) Re(550).ltoreq.10 nm and
|Rth(550)|.ltoreq.10 nm Expression (Y) ##STR00001##
Inventors: |
ISHIGURO; Makoto; (Kanagawa,
JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
FUJIFILM Corporation |
Tokyo |
|
JP |
|
|
Assignee: |
FUJIFILM Corporation
Tokyo
JP
|
Family ID: |
52813174 |
Appl. No.: |
15/092051 |
Filed: |
April 6, 2016 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
PCT/JP2014/077053 |
Oct 9, 2014 |
|
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15092051 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
G02B 5/3025 20130101;
G02F 2201/50 20130101; G02B 1/14 20150115; B32B 27/06 20130101;
G02B 5/3033 20130101; C08F 222/1006 20130101; B32B 2307/536
20130101; B32B 7/02 20130101; B32B 2307/71 20130101; B32B 27/308
20130101; C08F 230/06 20130101; G02B 5/208 20130101; G02B 5/3083
20130101; B32B 2307/42 20130101; B32B 2457/20 20130101; G02F
1/133528 20130101 |
International
Class: |
G02B 1/14 20060101
G02B001/14; G02B 5/20 20060101 G02B005/20; G02F 1/1335 20060101
G02F001/1335; G02B 5/30 20060101 G02B005/30 |
Foreign Application Data
Date |
Code |
Application Number |
Oct 9, 2013 |
JP |
2013-212188 |
Dec 25, 2013 |
JP |
2013-267617 |
Claims
1. A polarizing plate, comprising: a polarizer; and a resin layer
directly in contact with the polarizer, wherein the resin layer is
a layer obtained by polymerizing and curing a boronic acid monomer
having a boronic acid group denoted by Formula (1) and a
polymerizable group, and a multifunctional monomer, Re(550) and
Rth(550) of the resin layer respectively satisfy Expression (X) and
Expression (Y) described below, Re(550).ltoreq.10 nm Expression (X)
|Rth(550)|.ltoreq.10 nm Expression (Y) a thickness of the polarizer
is less than or equal to 35 .mu.m, Re(550) indicates in-plane
retardation (nm) at a wavelength of 550 nm, and Rth(550) indicates
retardation (nm) in a thickness direction at a wavelength of 550
nm, and ##STR00022## in Formula (1), R.sup.1 and R.sup.2 each
independently represent a hydrogen atom, a substituted or
unsubstituted aliphatic hydrocarbon group, an aryl group, or a
heterocyclic group, R.sup.1 and R.sup.2 may be connected to each
other to form a ring, and * indicates a bonding position.
2. The polarizing plate according to claim 1, wherein a mass ratio
of the boronic acid monomer to the total mass of the boronic acid
monomer and the multifunctional monomer (a mass of the boronic acid
monomer/(the total mass of the boronic acid monomer and the
multifunctional monomer)) is 0.005 mass % to 11.0 mass %.
3. The polarizing plate according to claim 1, wherein the
polymerizable group included in the multifunctional monomer is a
(meth)acryloyl group.
4. The polarizing plate according to claim 1, wherein the resin
layer further contains an ultraviolet absorbent.
5. The polarizing plate according to claim 1, wherein maximum
transmittance of the resin layer at a wavelength of 300 nm to 380
nm is less than or equal to 15%.
6. The polarizing plate according to claim 1, further comprising: a
polarizer protective film on a surface of the polarizer on a side
opposite to the resin layer side, wherein maximum transmittance of
the polarizer protective film at a wavelength of 300 nm to 380 nm
is less than or equal to 15%.
7. An image display device, comprising: the polarizing plate
according to claim 1.
8. The image display device according to claim 7, wherein the image
display device is a liquid crystal display device.
9. The polarizing plate according to claim 2, wherein the
polymerizable group included in the multifunctional monomer is a
(meth)acryloyl group.
10. The polarizing plate according to claim 2, wherein the resin
layer further contains an ultraviolet absorbent.
11. The polarizing plate according to claim 3, wherein the resin
layer further contains an ultraviolet absorbent.
12. The polarizing plate according to claim 2, wherein maximum
transmittance of the resin layer at a wavelength of 300 nm to 380
nm is less than or equal to 15%.
13. The polarizing plate according to claim 3, wherein maximum
transmittance of the resin layer at a wavelength of 300 nm to 380
nm is less than or equal to 15%.
14. The polarizing plate according to claim 4, wherein maximum
transmittance of the resin layer at a wavelength of 300 nm to 380
nm is less than or equal to 15%.
15. The polarizing plate according to claim 2, further comprising:
a polarizer protective film on a surface of the polarizer on a side
opposite to the resin layer side, wherein maximum transmittance of
the polarizer protective film at a wavelength of 300 nm to 380 nm
is less than or equal to 15%.
16. The polarizing plate according to claim 3, further comprising:
a polarizer protective film on a surface of the polarizer on a side
opposite to the resin layer side, wherein maximum transmittance of
the polarizer protective film at a wavelength of 300 nm to 380 nm
is less than or equal to 15%.
17. The polarizing plate according to claim 4, further comprising:
a polarizer protective film on a surface of the polarizer on a side
opposite to the resin layer side, wherein maximum transmittance of
the polarizer protective film at a wavelength of 300 inn to 380 nm
is less than or equal to 15%.
18. An image display device, comprising: the polarizing plate
according to claim 2.
19. An image display device, comprising: the polarizing plate
according to claim 3.
20. An image display device, comprising: the polarizing plate
according to claim 4.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a Continuation of PCT International
Application No. PCT/JP2014/077053 filed on Oct. 9, 2014, which
claims priority under 35 U.S.C. .sctn.119(a) to Japanese Patent
Application No. 2013-212188 filed on Oct. 9, 2013 and Japanese
Patent Application No. 2013-267617 filed on Dec. 25, 2013. Each of
the above applications is hereby expressly incorporated by
reference, in its entirety, into the present application.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to a polarizing plate, and in
particular, the present invention relates to a polarizing plate
including a resin layer formed by polymerizing and curing a boronic
acid monomer and a multifunctional monomer, and an image display
device including the polarizing plate.
[0004] 2. Description of the Related Art
[0005] In general, a polarizer has low mechanical strength, and
thus, has been used as a polarizing plate by bonding a polarizer
protective film such as a film formed of triacetyl cellulose which
is subjected to a saponification treatment to the polarizer.
[0006] On the other hand, recently, in the polarizer protective
film, improvement in various performances such as improvement in
mechanical strength has been required, and various proposals have
been made. For example, in JP2011-221185A, a polarizing plate is
disclosed in which a curable resin layer formed of a curable resin
composition containing a multifunctional (meth)acrylic monomer is
directly formed on the surface of a polarizer. According to this
polarizing plate, adhesiveness between the polarizer and the
curable resin layer is high, and surface hardness is also
excellent.
SUMMARY OF THE INVENTION
[0007] On the other hand, a thinner polarizer has been required,
and further improvement in surface hardness of the polarizing plate
and further improvement in adhesiveness between the polarizer and
the polarizer protective film have been required according to the
expansion of applications of image display devices such as a liquid
crystal display device or an organic EL display device.
[0008] The present inventors have conducted studies about
properties of the polarizing plate including the curable resin
layer disclosed in JP2011-221185A, and thus, have found that the
adhesiveness between the polarizer and the curable resin layer does
not satisfy the levels required these days and further improvement
is required.
[0009] In consideration of the circumstances described above, an
object of the present invention is to provide a polarizing plate
having excellent surface hardness and excellent adhesiveness
between a polarizer and a resin layer arranged on the
polarizer.
[0010] In order to attain the object described above, the present
inventors have conducted intensive studies, and thus, have found
that the object described above is able to be attained by using a
predetermined boronic acid monomer, and have completed the present
invention.
[0011] That is, the present inventors have found that the object
described above is able to be attained by the following
configurations.
[0012] (1) A polarizing plate including a polarizer; and a resin
layer directly in contact with the polarizer, in which the resin
layer is a layer obtained by polymerizing and curing a boronic acid
monomer having a boronic acid group denoted by Formula (1)
described below and a polymerizable group, and a multifunctional
monomer, Re(550) and Rth(550) of the resin layer respectively
satisfy Expression (X) and Expression (Y) described below, and
Re(550).ltoreq.10 nm Expression (X)
|Rth(550)|.ltoreq.10 nm Expression (Y)
[0013] a thickness of the polarizer is less than or equal to 35
.mu.m.
[0014] (Here, Re(550) indicates in-plane retardation (nm) at a
wavelength of 550 nm, and Rth(550) indicates retardation (nm) in a
thickness direction at a wavelength of 550 nm.)
[0015] (2) The polarizing plate according to [1], in which a mass
ratio of the boronic acid monomer to the total mass of the boronic
acid monomer and the multifunctional monomer (a mass of the boronic
acid monomer/(the total mass of the boronic acid monomer and the
multifunctional monomer)) is 0.005 mass % to 11.0 mass %.
[0016] (3) The polarizing plate according to [1] or [2], in which
the polymerizable group included in the multifunctional monomer is
a (meth)acryloyl group.
[0017] (4) The polarizing plate according to any one of [1] to [3],
in which the resin layer further contains an ultraviolet
absorbent.
[0018] (5) The polarizing plate according to any one of [1] to [4],
in which maximum transmittance of the resin layer at a wavelength
of 300 nm to 380 nm is less than or equal to 15%.
[0019] (6) The polarizing plate according to any one of [1] to [4],
in which the polarizing plate further includes a polarizer
protective film on a surface of the polarizer on a side opposite to
the resin layer side, and maximum transmittance of the polarizer
protective film at a wavelength of 300 nm to 380 nm is less than or
equal to 15%.
[0020] (7) An image display device including the polarizing plate
according to any one of [1] to [6].
[0021] (8) The image display device according to [7], in which the
image display device is a liquid crystal display device.
[0022] According to the present invention, it is possible to
provide a polarizing plate having excellent surface hardness and
excellent adhesiveness between a polarizer and a resin layer
arranged on the polarizer.
BRIEF DESCRIPTION OF THE DRAWINGS
[0023] FIG. 1 is a sectional view of one embodiment of a polarizing
plate of the present invention.
[0024] FIG. 2 is a sectional view of the other embodiment of the
polarizing plate of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0025] Hereinafter, the present invention will be described in
detail. Further, herein, a numerical range denoted by using "to"
indicates a range including numerical values before and after "to"
as the lower limit value and the upper limit value.
[0026] Examples of a characteristic point of the present invention
include a point in which a layer obtained by polymerizing and
curing a predetermined boronic acid monomer and a multifunctional
monomer is arranged to be directly in contact with the surface of a
polarizer.
[0027] In the present invention, a mechanism of obtaining a desired
effect is assumed as follows. In the present invention, the boronic
acid monomer and the multifunctional monomer is directly
polymerized and cured on the polarizer, first, the boronic acid
monomer forms a bond with the polarizer through the boronic acid
group, and is unevenly distributed on the surface of the polarizer.
Next, at the time of polymerizing and curing, a polymerizable group
in the multifunctional monomer reacts with a polymerizable group in
the boronic acid monomer which is bonded to the polarizer. That is,
it is considered that the boronic acid monomer is bonded to both of
the polarizer and the multifunctional monomer in the resin layer,
and a function of increasing adhesiveness between the polarizer and
the resin layer is obtained.
[0028] Hereinafter, one embodiment of a polarizing plate of the
present invention will be described with reference to the drawings.
FIG. 1 illustrates a sectional view of one embodiment of the
polarizing plate of the present invention. Further, the drawing of
the present invention is a schematic view, and a relationship
between thicknesses of respective layers, a position relationship,
or the like is not necessarily coincident with the actual
relationship. The same applies to the following drawings.
[0029] A polarizing plate 10 includes a polarizer 12 and a resin
layer 14. As illustrated in FIG. 1, the resin layer 14 is directly
arranged on the surface of the polarizer 12, and functions as a
polarizer protective film.
[0030] Hereinafter, each member of the polarizing plate (the
polarizer and the resin layer) will be described below.
[0031] <Polarizer>
[0032] The polarizer may be a member having a function of
converting light into specific linearly polarized light, and an
absorptive type polarizer and a reflective type polarizer are able
to be used.
[0033] An iodine-based polarizer, a dye-based polarizer using a
dichromatic dye, a polyene-based polarizer, and the like are used
as the absorptive type polarizer. The iodine-based polarizer and
the dye-based polarizer are a coating type polarizer and a
stretching type polarizer, any one of them is able to be applied,
and a polarizer which is prepared by allowing polyvinyl alcohol to
adsorb iodine or a dichromatic dye, and by performing stretching is
preferable.
[0034] In addition, examples of a method of obtaining a polarizer
by performing stretching and dyeing in a state of a laminated film
in which a polyvinyl alcohol layer is formed on a substrate are
able to include methods disclosed in JP5048120B, JP5143918B,
JP5048120B, JP4691205B, JP4751481B, and JP4751486B, and known
technologies related to these polarizers are able to be preferably
used.
[0035] A polarizer in which thin films having different
birefringence are laminated, a wire grid type polarizer, a
polarizer in which a cholesteric liquid crystal having a selective
reflection range and a 1/4 wavelength plate are combined, and the
like are used as the reflective type polarizer.
[0036] Among them, a polarizer containing a polyvinyl alcohol-based
resin (a polymer including --CH.sub.2--CHOH-- as a repeating unit,
in particular, at least one selected from the group consisting of
polyvinyl alcohol and an ethylene-vinyl alcohol copolymer) is
preferable from the viewpoint of more excellent adhesiveness with
respect to the resin layer described below.
[0037] The thickness of the polarizer is less than or equal to 35
.mu.m, is preferably 3 .mu.m to 25 .mu.m, and is more preferably 4
.mu.m to 15 .mu.m, from the viewpoint of excellent handleability
and excellent optical properties. According to the thickness
described above, it is possible to cope with the thinning of an
image display device.
[0038] <Resin Layer>
[0039] The resin layer (a curable resin layer) is a layer which
protects the polarizer and imparts mechanical strength to the
polarizing plate. Further, in FIG. 1, the resin layer 14 is
arranged only on one surface of the polarizer 12, and may be
arranged on both surfaces.
[0040] The resin layer is a layer which is directly in contact with
the polarizer, and is a layer obtained by polymerizing and curing a
boronic acid monomer having a boronic acid group denoted by Formula
(1) and a polymerizable group, and a multifunctional monomer. In
addition, the resin layer exhibits optical isotropy.
[0041] Hereinafter, first, a raw material of the resin layer (the
boronic acid monomer, the multifunctional monomer, and the like)
will be described in detail, and after that, a manufacturing
procedure or the like of the resin layer will be described in
detail.
[0042] (Boronic Acid Monomer)
[0043] The boronic acid monomer is a compound having a boronic acid
group denoted by Formula (1) and a polymerizable group, and as
described above, has a function of increasing adhesiveness between
the polarizer and the resin layer.
##STR00002##
[0044] In Formula (1), R.sup.1 and R.sup.2 each independently
represent a hydrogen atom, a substituted or unsubstituted aliphatic
hydrocarbon group, an aryl group, or a heterocyclic group.
[0045] Examples of the aliphatic hydrocarbon group include a
substituted or unsubstituted straight chain or branched alkyl group
having 1 to 20 carbon atoms (for example, a methyl group, an ethyl
group, an iso-propyl group, and the like), a substituted or
unsubstituted cyclic alkyl group having 3 to 20 carbon atoms (for
example, a cyclohexyl group, and the like), and an alkenyl group
having 2 to 20 carbon atoms (for example, a vinyl group, and the
like).
[0046] Examples of the aryl group include a substituted or
unsubstituted phenyl group having 6 to 20 carbon atoms (for
example, a phenyl group, a tolyl group, and the like), a
substituted or unsubstituted naphthyl group having 10 to 20 carbon
atoms, and the like.
[0047] The heterocyclic group is a substituted or unsubstituted
group having a 5-membered ring or a 6-membered ring which includes
at least one hetero atom (for example, a nitrogen atom, an oxygen
atom, a sulfur atom, and the like), and examples of the
heterocyclic group include a pyridyl group, an imidazolyl group, a
furyl group, a piperidyl group, a morpholino group, and the
like.
[0048] R.sup.1 and R.sup.2 may be connected to each other to form a
ring, and for example, isopropyl groups of R.sup.1 and R.sup.2 may
be connected to each other to form a
4,4,5,5-tetramethyl-1,3,2-dioxaborolane ring.
[0049] In Formula (1), the hydrogen atom, the straight chain or
branched alkyl group having 1 to 3 carbon atoms, and the ring
formed by connecting R.sup.1 and R.sup.2 to each other are
preferable as R.sup.1 and R.sup.2, and the hydrogen atom is
particularly preferable.
[0050] In Formula (1), * represents a bonding position.
[0051] Further, the number of boronic acid groups denoted by
Formula (1) is not particularly limited, and one boronic acid group
may be included, or a plurality of (two or more) boronic acid
groups may be included.
[0052] Further, one or more hydrocarbon groups included in the
aliphatic hydrocarbon group, the aryl group, and the heterocyclic
group may be substituted with an arbitrary substituent group.
Examples of the type of substituent group include a substituent
group disclosed in paragraph "0046" of JP2013-054201A.
[0053] The type of polymerizable group is not particularly limited,
and examples of the type of polymerizable group include a radical
polymerizable group, a cation polymerizable group, and the like.
Examples of the radical polymerizable group include a
(meth)acryloyl group, an acryl amide group, a vinyl group, a styryl
group, an allyl group, and the like. Examples of the cation
polymerizable group include a vinyl ether group, an oxiranyl group,
an oxetanyl group, and the like. Among them, the (meth)acryloyl
group, the styryl group, the vinyl group, the oxiranyl group, or
the oxetanyl group is preferable, the (meth)acryloyl group or the
styryl group is more preferable, or the (meth)acryloyl group is
particularly preferable.
[0054] Further, the (meth)acryloyl group is the concept including
both of an acryloyl group and a methacryloyl group.
[0055] The number of polymerizable groups is not particularly
limited, and one polymerizable group may be included, or a
plurality of (two or more) polymerizable groups may be
included.
[0056] The molecular weight of the boronic acid monomer is not
particularly limited, and is preferably 120 to 1200, and is more
preferably 180 to 800, from the viewpoint of excellent
compatibility with respect to the multifunctional monomer.
[0057] Examples of a preferred embodiment of the boronic acid
monomer include a boronic acid monomer denoted by Formula (2) from
the viewpoint of more excellent adhesiveness between the polarizer
and the resin layer.
##STR00003##
[0058] The definition of R.sup.1 and R.sup.2 of Formula (2) is as
described above.
[0059] Z represents a polymerizable group. The definition of the
polymerizable group is as described above.
[0060] X.sup.1 represents a single bond or a divalent linking
group. Examples of the divalent linking group include --O--,
--CO--, --NH--, --CONH--, --OCONH--, --COO--, --O--COO--, an
alkylene group, an arylene group, a heterocyclic group (a hetero
arylene group), and a divalent linking group selected from a
combination thereof.
[0061] Further, examples of the combination include -arylene
group-La-arylene group-La-arylene group-La-alkylene group-,
-arylene group-La-arylene group-La-alkylene group-, -arylene
group-La-alkylene group-, and the like. La represents --COO--,
--CO--NH--, --O--, or --OCONH--.
[0062] Hereinafter, a specific example of the boronic acid monomer
will be described, but the present invention is not limited
thereto.
##STR00004## ##STR00005##
[0063] (Multifunctional Monomer)
[0064] The multifunctional monomer is a compound which is able to
be polymerized by light or heat, and is a component configuring the
resin layer by being polymerized and cured.
[0065] A plurality of polymerizable groups are included in the
multifunctional monomer. The definition of the polymerizable group
is as described above, and the (methyl)acryloyl group is
preferable.
[0066] The number of polymerizable groups are included in the
multifunctional monomer is not particularly limited, a plurality of
(two or more) polymerizable groups may be included, and the number
of polymerizable groups is preferably 3 to 32, and is more
preferably 3 to 20, from the viewpoint of more excellent surface
hardness of the polarizing plate.
[0067] Specific examples of the multifunctional monomer are able to
include multifunctional (meth)acrylate obtained by performing an
addition reaction of ethylene oxide or propylene oxide with respect
to multifunctional alcohol such as ethylene glycol
di(meth)acrylate, triethylene glycol di(meth)acrylate,
tetramethylene glycol di(meth)acrylate, propylene glycol
di(meth)acrylate, polyethylene glycol di(meth)acrylate,
polypropylene glycol di(meth)acrylate, 1,3-butanediol
di(meth)acrylate, trimethylol ethane triacrylate, trimethylol
propane tri(meth)acrylate, trimethylol propane di(meth)acrylate,
neopentyl glycol di(meth)acrylate, pentaerythritol
tetra(meth)acrylate, pentaerythritol tri(meth)acrylate,
pentaerythritol hexa(meth)acrylate, dipentaerythritol
hexa(meth)acrylate, dipentaerythritol penta(meth)acrylate,
hexanediol di(meth)acrylate, trimethylol propane tri(acryloyl oxy
propyl) ether, tri(acryloyl oxy ethyl) isocyanurate, tri(acryloyl
oxy ethyl) cyanurate, glycerin tri(meth)acrylate, trimethylol
propane, or glycerin, and then by performing (meth)acrylation.
[0068] Only one type of the multifunctional monomer may be used, or
two or more types thereof may be used in combination.
[0069] Further, the (meth)acrylate is the concept including both of
acrylate and methacrylate.
[0070] A mass ratio of the boronic acid monomer and the
multifunctional monomer described above is not particularly
limited, and the mass ratio of the boronic acid monomer to the
total mass of the boronic acid monomer and the multifunctional
monomer (the mass of the boronic acid monomer/(the total mass of
the boronic acid monomer and the multifunctional monomer)) is
preferably 0.0005 mass % to 20.0 mass %, is more preferably 0.005
mass % to 11.0 mass %, and is even more preferably 0.05 mass % to
9.0 mass %, from the viewpoint of more excellent durability of the
polarizer of the polarizing plate in high temperature high humidity
conditions.
[0071] (Manufacturing Method of Resin Layer)
[0072] A manufacturing method of the resin layer is not
particularly limited insofar as the resin layer which is directly
in contact with the polarizer is able to be manufactured, and the
resin layer is able to be manufactured by directly applying a
composition for forming a resin layer containing the boronic acid
monomer described above and the multifunctional monomer described
above onto the polarizer, and by polymerizing and curing the
composition, from the viewpoint of more easily controlling the
thickness of the resin layer. In other words, an embodiment is
preferable in which a coated film is formed by directly applying
the composition for forming a resin layer onto the polarizer, a
polymerizing and curing treatment is performed with respect to the
coated film, and thus, the resin layer is manufactured.
[0073] Hereinafter, the embodiment using the composition for
forming a resin layer will be described in detail.
[0074] The composition for forming a resin layer contains the
boronic acid monomer described above and the multifunctional
monomer described above. A mass ratio of the boronic acid monomer
and the multifunctional monomer is not particularly limited, and it
is preferable that the mass ratio satisfies the mass ratio of the
boronic acid monomer (the mass of the boronic acid monomer/(the
total mass of the boronic acid monomer and the multifunctional
monomer)).
[0075] In addition, the composition for forming a resin layer may
contain components other than the boronic acid monomer described
above and the multifunctional monomer described above.
[0076] For example, the composition for forming a resin layer may
contain a polymerization initiator.
[0077] The type of polymerization initiator is not particularly
limited, and an optimal compound is suitably selected according to
the type of polymerizing and curing. More specifically, examples of
the polymerization initiator include a photopolymerization
initiator and a thermal polymerization initiator.
[0078] Examples of the photopolymerization initiator include an
alkyl phenone-based photopolymerization initiator, an acyl
phosphine oxide-based photopolymerization initiator, a
titanocene-based photopolymerization initiator, and the like.
Examples of the thermal polymerization initiator include a ketone
peroxide-based thermal polymerization initiator, a peroxy
ketal-based thermal polymerization initiator, a hydroperoxide-based
thermal polymerization initiator, a dialkyl peroxide-based thermal
polymerization initiator, a diacyl peroxide-based thermal
polymerization initiator, a peroxy dicarbonate-based thermal
polymerization initiator, a peroxy ester-based thermal
polymerization initiator, and the like.
[0079] The composition for forming a resin layer may contain
various surfactants.
[0080] The surfactant is able to suppress film thickness unevenness
due to a drying variation of local distribution of drying air, and
to suppress surface concavities and convexities of the resin layer
or a variation in a coating material (function as a leveling
agent).
[0081] Specifically, a fluorine-based surfactant or a
silicone-based surfactant is preferable as the surfactant. In
addition, it is preferable that the surfactant is an oligomer or a
polymer rather than a low molecular compound.
[0082] In a case where the surfactant is added, the surfactant is
rapidly moved and unevenly distributed on the coated surface of a
liquid film, and the surfactant is still unevenly distributed on
the surface even after drying the film, and thus, the surface
energy of the resin layer to which the surfactant is added
decreases by the surfactant. It is preferable that the surface
energy of the film is low from the viewpoint of preventing film
thickness inhomogeneity or variation, and unevenness of the resin
layer.
[0083] Preferred embodiments and specific examples of the
fluorine-based surfactant are disclosed in paragraphs [0023] to
[0080] of JP2007-102206A, and the same applies to the present
invention.
[0084] Preferred examples of the silicone-based surfactant include
a silicone-based surfactant having a substituent group on a
terminal of a chain and/or on a side chain of a compound having a
plurality of dimethyl silyloxy units as a repeating unit. A
structural unit other than the dimethyl silyloxy unit may be
included on the chain of the compound having a dimethyl silyloxy
unit as a repeating unit. The substituent groups may be identical
to each other or different from each other, and a plurality of
substituent groups are preferable. Examples of a preferred
substituent group include a group including a polyether group, an
alkyl group, an aryl group, an aryloxy group, a cynnamoyl group, an
oxetanyl group, a fluoroalkyl group, a polyoxy alkylene group, and
the like.
[0085] Examples of a preferred silicone-based surfactant include
"X-22-174DX", "X-22-2426", "X22-164C", and "X-22-176D" (all are
product names) manufactured by Shin-Etsu Chemical Co., Ltd.;
"FM-7725", "FM-5521", and "FM-6621" (all are product names)
manufactured by CHISSO CORPORATION; "DMS-U22" and "RMS-033" (all
are product names) manufactured by Gelest, Inc.; "SH200", "DC11PA",
"ST80PA", "L7604", "FZ-2105", "L-7604", "Y-7006", and "SS-2801"
(all are product names) manufactured by Dow Corning Toray Co.,
Ltd.; "TSF400" (Product Name) manufactured by Momentive Performance
Materials Inc.; and the like, but are not limited thereto.
[0086] The molecular weight of the surfactant is not particularly
limited, and is preferably less than or equal to 100,000, is more
preferably less than or equal to 50,000, is particularly preferably
1,000 to 30,000, and is most preferably 1,000 to 20,000.
[0087] The content of the surfactant in the composition for forming
a resin layer is not particularly limited, and the content of the
surfactant with respect to the total mass of the resin layer to be
formed is preferably adjusted to be 0.01 mass % to 0.5 mass %, and
is more preferably adjusted to be 0.01 mass % to 0.3 mass %.
[0088] (Translucent Resin Particles)
[0089] In addition, in order to impart anti-glare characteristics
(surface scattering properties) or internal scattering properties,
various translucent resin particles are able to be used in the
resin layer.
[0090] In the translucent resin particles, a variation in
scattering properties decreases as a variation in a particle
diameter becomes smaller, and a haze value is easily designed.
Plastic beads are preferable as the translucent resin
particles.
[0091] Organic particles are exemplified as the translucent resin
particles, and polymethyl methacrylate particles (a refractive
index of 1.49), cross-linking poly(acryl-styrene) copolymer
particles (a refractive index of 1.54), melamine resin particles (a
refractive index of 1.57), polycarbonate particles (a refractive
index of 1.57), polystyrene particles (a refractive index of 1.60),
cross-linking polystyrene particles (a refractive index of 1.61),
polyvinyl chloride particles (a refractive index of 1.60),
benzoguanamine-melamine formaldehyde particles (a refractive index
of 1.68), and the like are used as the organic particles.
[0092] Among them, the cross-linking polystyrene particles, the
cross-linking poly((meth)acrylate) particles, and the cross-linking
poly(acryl-styrene) particles are preferably used, the refractive
index of a resin component of the resin layer is adjusted according
to the refractive index of each of the translucent resin particles
selected from the particles described above, and thus, anti-glare
characteristics (surface scattering properties) or internal
scattering properties are able to be imparted. Further, an inside
haze, a surface haze, and center line average roughness are able to
be preferably attained.
[0093] A difference in the refractive indices between the resin
component of the resin layer and the translucent resin particles
(the refractive index of the translucent resin particles--the
refractive index of the resin component in the resin layer) is
preferably 0.001 to 0.030 as an absolute value. In a case where the
difference in the refractive indices is in the range described
above, problems such as blurred characters of the film, a decrease
in dark room contrast, and cloudiness of the surface do not
occur.
[0094] It is preferable that the average particle diameter (on the
basis of volume) of the translucent resin particles is 0.5 .mu.m to
20 .mu.m. In a case where the average particle diameter is in the
range described above, a scattering angle distribution of light is
in a wide angle, and thus, blurred characters of a display do not
occur.
[0095] In addition, two or more types of translucent resin
particles having different particle diameters may be used in
combination. The translucent resin particles having a larger
particle diameter are able to impart anti-glare characteristics,
and the translucent resin particles having a smaller particle
diameter are able to reduce graininess of the surface.
[0096] When the translucent resin particles are formulated, it is
preferable that the translucent resin particles are formulated in
the total solid content of the resin layer such that the content is
3 mass % to 30 mass %. When the content is in the range described
above, problems such as image blur or cloudiness or dazzling of the
surface are able to be prevented.
[0097] In addition, in the image display device, a layer of low
refractive index may be disposed on the resin layer arranged on a
visible side. More preferably, a layer of intermediate refractive
index and a layer of high refractive index may be disposed between
the resin layer and the layer of low refractive index. By
laminating a layer having a different refractive index on the resin
layer, it is possible to increase antireflection properties.
[0098] Preferred embodiments and specific examples of the layer of
low refractive index, the layer of intermediate refractive index,
and the layer of high refractive index are disclosed in paragraphs
[0237] to [0250] of JP2007-102206A, and the same applies to the
present invention.
[0099] The composition for forming a resin layer may contain a
solvent, as necessary. Examples of the solvent include water or an
organic solvent.
[0100] In addition, various additives other than the additives
described above are able to be added to the composition for forming
a resin layer within a range not impairing the properties thereof.
An ultraviolet absorbent, an antioxidant, a light stabilizer, an
organic/mineral filler, a plasticizer, a flame retardant, a heat
stabilizer, a lubricant, an antistatic agent, a release agent, a
foaming agent, a nucleating agent, a coloring agent, a
cross-linking agent, a dispersion aid, a leveling agent, a resin
component, and the like are able to be exemplified as the various
additives.
[0101] A method of applying the composition for forming a resin
layer onto the polarizer is not particularly limited, and a known
coating method is able to be adopted. Examples of the coating
method include gravure coating, roll coating, reverse coating,
knife coating, die coating, lip coating, doctor coating, extrusion
coating, slide coating, wire bar coating, curtain coating, spinner
coating, and the like.
[0102] In order to remove the solvent, a drying treatment may be
performed with respect to a coating layer of the composition after
applying the composition for forming a resin layer, as necessary. A
drying treatment method is not particularly limited, and examples
of the drying treatment method include an air drying treatment, a
heating treatment, and the like.
[0103] A method of polymerizing and curing the coating layer of the
composition obtained by the coating described above is not
particularly limited, and examples of the method include a heating
treatment, a light irradiation treatment, and the like.
[0104] The conditions of the heating treatment are different
according to a material to be used, and a treatment of 40.degree.
C. to 120.degree. C. (preferably 50.degree. C. to 80.degree. C.)
for 0.5 minutes to 10 minutes (preferably 1 minute to 5 minutes) is
preferable from the viewpoint of more excellent reaction
efficiency.
[0105] The conditions of the light irradiation treatment are not
particularly limited, and an ultraviolet ray irradiation method of
generating and emitting an ultraviolet ray and performing
photocuring is preferable. Examples of an ultraviolet ray lamp used
in such a method include a metal halide lamp, a high pressure
mercury lamp, a low pressure mercury lamp, a pulse type xenon lamp,
a xenon/mercury mixed lamp, a low pressure sterilization lamp, and
an electrodeless lamp. Among the ultraviolet ray lamps, it is
preferable that the metal halide lamp or the high pressure mercury
lamp is used.
[0106] In addition, irradiation conditions are different according
to the conditions of each of the lamps, and in general, an
irradiation exposure amount may be in a range of 20 mJ/cm.sup.2 to
10000 mJ/cm.sup.2, and it is preferable that the irradiation
exposure amount is in a range of 100 mJ/cm.sup.2 to 3000
mJ/cm.sup.2.
[0107] The average thickness of the resin layer obtained by the
treatment described above is not particularly limited, and is
preferably 0.2 .mu.m to 15 .mu.m, and is more preferably 0.5 .mu.m
to 10 .mu.m, from the viewpoint of handleability.
[0108] The film thickness is able to be measured by using an
existing film thickness meter and reflective spectrographic film
thickness meter (FE-3000, manufactured by OTSUKA ELECTRONICS Co.,
LTD.). Alternatively, the sectional surface of the resin layer may
be directly measured by being observed using a microscope or
SEM.
[0109] Further, the average thickness is a value obtained by
measuring the thicknesses of arbitrary five or more points which
are separated from each other by greater than or equal to 10 mm in
the resin layer, and by performing arithmetic averaging with
respect to the thicknesses.
[0110] In addition, the resin layer satisfies Expression (X) and
Expression (Y) described below. Further, Expression (Y) indicates
that the absolute value of Rth(550) is less than or equal to 10 nm,
and in other words, indicates -10 nm.ltoreq.Rth(550).ltoreq.10
nm.
Re(550).ltoreq.10 nm Expression (X)
|Rth(550)|.ltoreq.10 nm Expression (Y)
[0111] Here, Re(550) indicates in-plane retardation (nm) at a
wavelength of 550 nm, and Rth(550) indicates retardation (nm) in a
thickness direction at a wavelength of 550 nm.
[0112] From the viewpoint of suppressing an influence on polarized
light to be transmitted through the resin layer, Re(550) of the
resin layer is preferably less than or equal to 5 nm, and is more
preferably less than or equal to 3 nm. In addition, by the same
reasons, |Rth(550)| of the resin layer is preferably less than or
equal to 5 nm, and is more preferably less than or equal to 3
nm.
[0113] Re(550) and Rth(550) of the resin layer are able to be
measured by using a retardation measurement device such as KOBRA
21ADH or WR (manufactured by Oji Scientific Instruments Co., Ltd.)
and AXOSCAN (manufactured by AXOMETRICS Inc.), as a measurement
method of Re(550) and Rth(550) of the resin layer.
[0114] The resin layer is a layer obtained by polymerizing and
curing the boronic acid monomer described above and the
multifunctional monomer described above, and may contain other
components.
[0115] For example, the resin layer may not contain the ultraviolet
absorbent.
[0116] A known ultraviolet absorbent is able to be used as the
ultraviolet absorbent. Examples of the ultraviolet absorbent
include a benzotriazole-based ultraviolet absorbent, a
benzophenone-based ultraviolet absorbent, a phenyl salicylate
ester-based ultraviolet absorbent, and a triazine-based ultraviolet
absorbent.
[0117] The content of the ultraviolet absorbent in the resin layer
is not particularly limited, and is preferably 2 mass % to 25 mass
% with respect to the total mass of the resin layer, from the
viewpoint of preventing the burst of the ultraviolet absorbent from
the resin layer after being polymerized and cured, of increasing
hardness of the resin layer, and of obtaining a balance between
visibility and UV shielding properties.
[0118] The optical properties of the resin layer are not
particularly limited, and in a case where the polarizing plate is
used in the image display device, and the resin layer is arranged
on the visible side, the maximum transmittance at a wavelength of
300 nm to 380 nm is preferably less than or equal to 15%, and is
more preferably less than or equal to 10%, from the viewpoint of
more excellent light resistance of the polarizer in the polarizing
plate.
[0119] The maximum transmittance is able to be measured by using a
spectrophotometer such as a spectrophotometer UV-3150 (manufactured
by Shimadzu Corporation), as a measurement method of the maximum
transmittance.
[0120] <Polarizing Plate and Application Thereof>
[0121] As described above, the polarizing plate of the present
invention includes at least the polarizer and the resin layer.
[0122] In a case where the polarizing plate is included in the
image display device, the resin layer may be arranged to be
directed towards the visible side (an outer side), or may be
arranged to be directed towards the opposite side (an inner
side).
[0123] Further, other layers may be included within a range not
impairing the effect of the present invention.
[0124] For example, as illustrated in FIG. 2, the image display
device may be a polarizing plate 100 in which a polarizer
protective film 16 is arranged on the surface of the polarizer 12
on a side opposite to the resin layer 14 side.
[0125] In a case where the polarizing plate including the polarizer
protective film is included in the image display device, it is
preferable that the polarizer protective film is arranged to be
directed towards the visible side (the outer side).
[0126] The optical properties of the polarizer protective film are
not particularly limited, and in a case where the polarizing plate
is used in the image display device, and the polarizer protective
film is arranged on the visible side, the maximum transmittance of
the polarizer protective film at a wavelength of 300 nm to 380 nm
is preferably less than or equal to 15%, and is more preferably
less than or equal to 7%, from the viewpoint of more excellent
light resistance of the polarizer in the polarizing plate.
[0127] The configuration of the polarizer protective film is not
particularly limited, and for example, the polarizer protective
film may be a so-called transparent support or hard coat layer, or
may be a laminated body of the transparent support and the hard
coat layer.
[0128] A known layer is able to be used as the hard coat layer, and
for example, the hard coat layer may be a layer obtained by
polymerizing and curing the multifunctional monomer described
above.
[0129] In addition, a known transparent support is able to be used
as the transparent support, and for example, a cellulose-based
polymer (hereinafter, referred to as cellulose acylate) represented
by triacetyl cellulose, a thermoplastic norbornene-based resin
(Zeonex and Zeonor manufactured by ZEON CORPORATION, Arton
manufactured by JSR Corporation, and the like), an acrylic resin,
and a polyester-based resin are able to be used as a material
forming the transparent support.
[0130] The thickness of the polarizer protective film is not
particularly limited, but is preferably less than or equal to 40
.mu.m, and is more preferably less than or equal to 25 .mu.m, from
the reason for enabling the thickness of the polarizing plate to be
thin.
[0131] By arranging the polarizing plate of the present invention
in an optical path of the image display device, for example, on one
side of at least one liquid crystal cell of a liquid crystal
display device, or the like, it is possible to obtain the image
display device of the present invention, for example, a liquid
crystal display device. The liquid crystal display device has
various modes according to the type of liquid crystal cell to be
used, and in any case, the polarizing plate of the present
invention is able to be used. For example, the polarizing plate of
the present invention is able to be used in the liquid crystal
display device of various modes such as a vertically aligned (VA)
mode, an in-plane switching (IPS) mode, an optically compensated
bend (OCB) mode, a twisted nematic (TN) mode, and a supertwisted
nematic (STN) mode.
[0132] Further, a retardation film for improving view angle
properties or contrast may be inserted between the polarizing plate
of the present invention and the liquid crystal cell. The
retardation film is different according to the type of liquid
crystal cell to be used, and in a case of a VA mode, a
negative-C-plate, an A-plate, a negative-C-plate, or the like is
used as the retardation film, in a case of an IPS mode, a
biaxial-plate, a positive-C-plate, or the like is used as the
retardation film, in a case of a TN mode, a film formed by
immobilizing a discotic liquid crystal which has been subjected to
hybrid alignment, or the like is used as the retardation film, and
in a case of a STN mode, a biaxial-plate, or the like is used as
the retardation film.
EXAMPLES
[0133] The characteristics of the present invention will be more
specifically described with reference to the following examples.
Materials, use amounts, ratios, treatment contents, treatment
procedures, and the like described in the following examples are
able to be suitably changed unless otherwise deviated from the
scope of the present invention. Therefore, the range of the present
invention will not be narrowly interpreted by the following
specific examples.
[0134] <Preparation of Film 28 with Hard Coat Layer>
[0135] (Preparation of Cellulose Ester Solution for Air Layer)
[0136] The following compositions were put into a mixing tank and
were stirred while being heated, each component was dissolved, and
thus, a cellulose ester solution for an air layer was prepared.
[0137] Composition of Cellulose Ester Solution for Air Layer
TABLE-US-00001 Cellulose Ester (Degree of Substitution of Acetyl of
2.86) 100 parts by mass Sugar Ester Compound of Formula (R-I) 3
parts by mass Sugar Ester Compound of Formula (R-II) 1 part by mass
Ultraviolet Absorbent Described below (Ultraviolet Absorbent X) 2.4
parts by weight Silica Particles Dispersion (Average Particle
Diameter of 16 nm) "AEROSIL R972" manufactured by NIPPON AEROSIL
CO., LTD, 0.026 parts by mass Methylene Chloride 339 parts by mass
Methanol 74 parts by mass Butanol 3 parts by mass ##STR00006##
##STR00007## Formula (R-I) ##STR00008## Formula (R-II) ##STR00009##
Ultraviolet Absorbent
[0138] (Preparation of Cellulose Ester Solution for Drum Layer)
[0139] The following compositions were put into a mixing tank and
were stirred while being heated, each component was dissolved, and
thus, a cellulose ester solution for a drum layer was prepared.
[0140] Composition of Cellulose Ester Solution for Drum Layer
TABLE-US-00002 Cellulose Ester (Degree of Substitution of 100 parts
by mass Acetyl 2.86) Sugar Ester Compound of Formula (R-I) 3 parts
by mass Sugar Ester Compound of Formula (R-II) 1 parts by mass
Ultraviolet Absorbent X Described above 2.4 parts by weight Silica
Particle Dispersion (average particle 0.091 parts by mass diameter
16 nm) "AEROSIL R972", manufactured by NIPPON AEROSIL CO., LTD.
Methylene Chloride 339 parts by mass Methanol 74 parts by mass
Butanol 3 parts by mass
[0141] (Preparation of Cellulose Ester Solution for Core Layer)
[0142] The following compositions were put into a mixing tank and
were stirred while being heated, each component was dissolved, and
thus, a cellulose ester solution for a core layer was prepared.
[0143] Composition of Cellulose Ester Solution for Core Layer
TABLE-US-00003 Cellulose Ester (Degree of Substitution of Acetyl
100 parts by mass 2.86) Sugar Ester Compound of Formula (R-II) 8.3
parts by mass Sugar Ester Compound of Formula (R-II) 2.8 parts by
mass Ultraviolet Absorbent X Described above 2.4 parts by weight
Methylene Chloride 266 parts by mass Methanol 58 parts by mass
Butanol 2.6 parts by mass
[0144] (Film Formation of Cocasting)
[0145] A device was used in which a feed block which had been
adjusted for cocasting was provided as a casting die, and thus, a
film having a three-layer structure was able to be molded. The
cellulose ester solution for an air layer, the cellulose ester
solution for a core layer, and the cellulose ester solution for a
drum layer were cocast onto a drum which had been cooled to
-7.degree. C. from a casting port. At this time, the flow rate of
each dope was adjusted such that a thickness ratio became the air
layer/the core layer/the drum layer=7/90/3.
[0146] The dope was cast onto a mirror stainless steel support
which was a drum having a diameter of 3 m. At this time, drying air
at 34.degree. C. was applied onto the drum at 270
m.sup.3/minute.
[0147] Then, a cellulose ester film which had been cast and rotated
from an end point of a casting unit to the front by 50 cm was
peeled off from the drum, and then, both ends of the film were
clipped by a pin tenter. At the time of peeling, stretching of 5%
was performed in a transportation direction (a longitudinal
direction).
[0148] A cellulose ester web retained by the pin tenter was
transported to a drying zone. In initial drying, drying air at
45.degree. C. was blown, and then, drying was performed at
110.degree. C. for 5 minutes. At this time, the cellulose ester web
was transported while being stretched in a width direction at a
stretching ratio of 10%.
[0149] In a case where the web was detached from the pin tenter, a
portion retained by the pin tenter was continuously cut, and
concavities and convexities having a width of 15 mm and a height of
10 .mu.m were applied to both end portions of the web in the width
direction. At this time, the width of the web was 1610 mm. Drying
was performed at 140.degree. C. for 10 minutes while applying
tensile stress of 210 N in the transportation direction. Further,
the end portions of the web in the width direction were
continuously cut such that the web had a desired width, and thus, a
cellulose ester film having a film thickness of 41 .mu.m was
prepared.
[0150] (Preparation of Hard Coat Layer)
[0151] The following curable resin compositions were prepared as a
coating liquid for forming a hard coat layer.
[0152] (Curable Resin Composition)
TABLE-US-00004 KAYARAD DPHA [manufactured by Nippon 48.5 parts by
mass Kayaku Co., Ltd.] KAYARAD PET30 [manufactured by Nippon 48.5
parts by mass Kayaku Co., Ltd.] Irgacure 127: Polymerization
Initiator 3.0 parts by mass [manufactured by BASF SE] Toluene 97.0
parts by mass Cyclohexane 3.0 parts by mass
[0153] The curable resin composition described above was applied
onto the cellulose ester film prepared as described above in
conditions of a transport speed of 30 m/minute by a die coating
method using a slot die disclosed in Example 1 of JP2006-122889A,
and was dried at 60.degree. C. for 60 seconds. After that, a
coating layer was cured by being irradiated with an ultraviolet ray
having illuminance of 400 mW/cm.sup.2 and irradiation dose of 390
mJ/cm.sup.2 under nitrogen purge (an oxygen concentration of
approximately 0.1%) by using an air-cooled metal halide lamp
(manufactured by EYE GRAPHICS Co., Ltd.) of 160 W/cm, and was
wound. The coating amount was adjusted such that the film thickness
of the curing layer became 4 .mu.m. Thus, a film 28 with a hard
coat layer (hereinafter, simply referred to as a "film 28") having
the total film thickness of 45 .mu.m was prepared.
[0154] <Preparation of Film 29 with Hard Coat Layer>
[0155] (Preparation of Acrylic Film)
[0156] A pellet of [a mixture of 90 parts by mass of an acrylic
resin having a lactone ring structure denoted by General Formula
(R-Ill) described below {Mass Ratio of Copolymerization
Monomer:Methyl Methacrylate/2-(Hydroxy Methyl) Methyl Acrylate=8/2,
a lactone cyclization rate of approximately 100%, a content ratio
of the lactone ring structure of 19.4%, a weight average molecular
weight of 133000, a melting flow rate of 6.5 g/10 minutes
(240.degree. C., 10 kgf), and Tg of 131.degree. C.}, 10 parts by
mass of an acrylonitrile-styrene (AS) resin {Toyo AS AS20,
manufactured by TOYO STYRENE CO., LTD.}, 4.5 parts by mass of
ADKSTAB LA-F70 {manufactured by ADEKA CORPORATION}; Tg of
127.degree. C.] was supplied to a biaxial extruder, and was melted
and extruded into the shape of a sheet at a temperature of
approximately 280.degree. C., and thus, a rectangular acrylic film
having a thickness of 20 .mu.m was obtained.
##STR00010##
[0157] In Formula (R-III) described above, R.sup.1 represents a
hydrogen atom, and R.sup.2 and R.sup.3 represent a methyl
group.
[0158] (Preparation of Hard Coat Layer)
[0159] A hard coat layer in which the film thickness of a curing
layer was 4 .mu.m was applied onto an acrylic film by the same
method as that of the film 28 with a hard coat layer except that
the cellulose ester film was changed to the acrylic film prepared
as described above in the film 28 with a hard coat layer. Thus, a
film 29 with a hard coat layer (hereinafter, simply referred to as
a "film 29") having the total film thickness of 24 .mu.m was
prepared.
[0160] <Polarizing Plate of Comparative Example 1>
[0161] The film 28 with a hard coat layer was prepared and was
dipped in an aqueous solution of NaOH of 1.5 mol/L (a
saponification liquid) held at 55.degree. C. for 2 minutes, and
after that, the film was washed with water. After that, the film
was dipped in an aqueous solution of a sulphuric acid of 0.05 mol/L
at 25.degree. C. for 30 seconds, and then, water washing was
performed under flowing water for 30 seconds, and thus, the film
was in a neutral state. Then, water draining was repeated three
times by using an air knife, the film was dried by being retained
in a drying zone at 70.degree. C. for 15 seconds after draining
water, and thus, a film which had been subjected to a
saponification treatment was prepared.
[0162] The saponified film 28 with a hard coat layer was bonded to
a polarizer (polyvinyl alcohol-based resin contain polarizer)
having a film thickness of 25 .mu.m by using a polyvinyl
alcohol-based adhesive agent, and was dried at 70.degree. C. for
greater than or equal to 10 minutes, and thus, a polarizing plate A
was prepared. Here, the polarizer was arranged such that a
transmission axis of the polarizer was orthogonal to the
transportation direction of the film. Further, at the time of
bonding, the film was bonded to the polarizer such that the film
side of the film 28 with a hard coat layer was directed towards the
polarizer side.
[0163] In the prepared polarizing plate A, a curable resin
composition 4 described below was applied onto the surface of the
polarizer on a side opposite to the film 28 with a hard coat layer
side in conditions of a transport speed of 24 m/minute by a die
coating method using a slot die disclosed in Example 1 of
JP2006-122889A, and was dried at 60.degree. C. for 60 seconds.
After that, a coating layer was cured by being irradiated with an
ultraviolet ray having illuminance of 400 mW/cm.sup.2 and
irradiation dose of 390 mJ/cm.sup.2 under nitrogen purge (an oxygen
concentration of approximately 0.1%) by using an air-cooled metal
halide lamp (manufactured by EYE GRAPHICS Co., Ltd.) of 160 W/cm
and was wound. The coating amount was adjusted such that the film
thickness of the curing layer became 1 .mu.m. Thus, a polarizing
plate of Comparative Example 1 was prepared.
[0164] (Curable Resin Composition 4) [0165] KAYARAD DPHA
[manufactured by Nippon Kayaku Co., Ltd.] 47.5 parts by mass [0166]
A-TMMT [manufactured by Shin Nakamura Chemical CO., LTD.] 47.5
parts by mass [0167] Irgacure 127: Polymerization Initiator
[manufactured by BASF SE] 5.0 parts by mass [0168] Methyl Ethyl
Ketone 100.0 parts by mass
Comparative Examples 2 to 5 and Examples 1 to 12 and 36 to 38
[0169] As shown in Table 2 described below, polarizing plates of
Comparative Examples 2 to 5 and Example 1 to 12 and 36 to 38 were
prepared by the same method as that in Comparative Example 1 except
that a curable resin composition shown in Table 1 described below
was used instead of the curable resin composition 4, and the type
of polarizer protective film and the thickness of the polarizer
were changed as shown in Table 2 described below.
[0170] Further, the configurations of Examples 1 to 12 and 36 to 38
correspond to the configuration illustrated in FIG. 2, and the
films 28 and 29 with a hard coat layer correspond to the polarizer
protective film 16 in FIG. 2.
[0171] In Table 1, the numerical values shown in the section of
"Composition" indicate parts by mass of the component.
[0172] Further, in each of the curable resin compositions, 100.0
parts by mass of methyl ethyl ketone is contained as a solvent.
[0173] In Table 1, DPHA, A-TMMT, and SP327 shown in the section of
"[A] Multifunctional Monomer" respectively indicate the
followings.
[0174] DPHA: KAYARAD DPHA [manufactured by Nippon Kayaku Co.,
Ltd.]
[0175] A-TMMT: A-TMMT [manufactured by Shin Nakamura Chemical CO.,
LTD.]
[0176] SP327: Compound described below manufactured by OSAKA
ORGANIC CHEMICAL INDUSTRY LTD.
##STR00011##
[0177] In Table 1, Compounds 1 to Compound 4 shown in the section
of "[B] Boronic Acid Monomer" respectively indicate the following
compounds.
##STR00012##
[0178] In Table 1, HBA and UV1700B shown in the section of "[C]
Other Monomers" respectively indicate the following compounds.
[0179] HBA: 4-Hydroxy Butyl Acrylate (manufactured by Nippon Kasei
Chemical Company Limited, Product Name of "HBA")
[0180] UV1700B: Polyurethane Acrylate (manufactured by The Nippon
Synthetic Chemical Industry Co., Ltd., Product Name of "Ultraviolet
Light UV-1700B")
[0181] In Table 1, Irg907 and Irg127 shown in the section of "[D]
Polymerization Initiator" respectively indicate the following
compounds.
[0182] Irg907: Irgacure 907 (manufactured by BASF SE)
[0183] Irg127: Irgacure 127 (manufactured by BASF SE)
[0184] In Table 1, Uvinul3050 and Tinuvin928 shown in the section
of "[E] Ultraviolet Absorbent" respectively indicate the following
compounds (manufactured by BASF SE).
##STR00013##
[0185] In Table 1, Compound 5 to Compound 7 shown in the section of
"[F] Surfactant" indicate a copolymer having a repeating unit shown
in Table 5 described below, at a content ratio (mol %) shown in
Table 5 described below. A weight average molecular weight (Mw) is
a measurement value of GPC measurement (in terms of
polystyrene).
TABLE-US-00005 TABLE 5 Compound 5 Compound 6 Compound 7
##STR00014## 25 ##STR00015## 25 ##STR00016## 90 ##STR00017## 90
##STR00018## 10 ##STR00019## 50 ##STR00020## ##STR00021## 10 Weight
Average 18000 13000 16000 Molecular Weight (Mw)
[0186] In Table 1, the section of "[B]/[A]+[B]" indicates the mass
ratio of the boronic acid monomer (the mass of the boronic acid
monomer/(the total mass of the boronic acid monomer and the
multifunctional monomer)).
[0187] In Table 1, the section of "Curing Layer" indicates
irradiation dose at the time of forming a resin layer by using each
curable resin composition, the film thickness of the resin layer
formed of each of the curable resin compositions, the maximum
transmittance of the resin layer formed of each of the curable
resin compositions, and each of Re(550) and Rth(550) of the resin
layer formed of each of the curable resin compositions.
[0188] The resin layer formed in each of the examples is
manufactured to have a film thickness shown in Table 1.
[0189] The maximum transmittance of the resin layer formed of each
of the curable resin compositions indicates the maximum
transmittance at a wavelength of 300 nm to 380 nm, and the maximum
transmittance was calculated by being measured by using UV-3150
(manufactured by Shimadzu Corporation).
[0190] Re(550) and Rth(550) of the resin layer formed of each of
the curable resin compositions were measured by AXOSCAN
(manufactured by AXOMETRICS Inc.).
[0191] Further, first, each of the curable resin compositions was
applied onto PET having a thickness of 100 .mu.m, and a coating
layer was cured by being irradiated with an ultraviolet ray having
illuminance of 400 mW/cm.sup.2 and irradiation dose of 390
mJ/cm.sup.2 under nitrogen purge (an oxygen concentration of
approximately 0.1%) by using an air-cooled metal halide lamp
(manufactured by EYE GRAPHICS Co., Ltd.) of 160 W/cm, and thus, a
resin layer was formed, as a measurement method of the maximum
transmittance, and Re(550) and Rth(550) of the resin layer. After
that, the PET was peeled off, and the maximum transmittance, and
Re(550) and Rth(550) only of the resin layer were measured.
Further, only in a case of curable resin compositions 15, 16, and
34, the irradiation dose was changed to 850 mJ/cm.sup.2. Further,
the thickness of each resin layer (cured film) was measured by the
film thickness (.mu.m) shown in Table 1.
[0192] In Table 2, the section of "Type of Curable Resin
Composition" indicates numbers of the curable resin compositions
shown in Table 1.
[0193] In addition, the section of "Resin Layer" indicates the
resin layer (the curing layer) obtained by the curable resin
composition, and for example, the resin layer formed of the curable
resin composition 1 indicates a curing layer 1.
[0194] In Table 2, the maximum transmittance of "Polarizer
Protective Film" indicates the maximum transmittance of the film 28
or the film 29 at a wavelength of 300 nm to 380 nm, and the maximum
transmittance was calculated by being measured by using UV-3150
(manufactured by Shimadzu Corporation).
TABLE-US-00006 TABLE 1 Composition (Part by Mass) Curing Layer [A]
[B] Boronic Acid Monomer [C] [D] [E] [F] Surfactant Irradi- Film
Maximum Multifunctional Com- Com- Com- Com- Other Polymerization
Ultraviolet Com- Com- Com- [B]/ ation Thick- Transmit- Re Rth
Monomer pound pound pound pound Monomers Initiator Absorbent pound
pound pound ([A] + Dose ness tance (550) (550) DPHA A-TMMT SP327 1
2 3 4 HBA UV1700B Irg907 Irg127 Uninul3050 Tinuvin928 5 6 7 [B])
(mJ) (.mu.m) (%) (nm) (nm) Curable Resin 54 -- -- -- -- -- -- 23 18
5.0 -- -- -- -- -- -- 0 390 1.0 92 0.1 0.9 Composition 1 Curable
Resin 64 -- -- -- -- -- -- 10 21 5.0 -- -- -- -- -- -- 0 390 1.0 92
0.1 0.9 Composition 2 Curable Resin 71 -- -- -- -- -- -- -- 24 5.0
-- -- -- -- -- -- 0 390 1.0 92 0.0 1.0 Composition 3 Curable Resin
47.5 47.5 -- -- -- -- -- -- -- -- 5.0 -- -- -- -- -- 0 390 1.0 92
0.0 1.0 Composition 4 Curable Resin 40 40 -- -- -- -- -- 15 -- --
5.0 -- -- -- -- -- 0 390 1.0 92 0.0 0.9 Composition 5 Curable Resin
43.3 43.3 -- 8.4 -- -- -- -- -- -- 5.0 -- -- -- -- -- 8.8 390 1.0
92 0.0 1.1 Composition 6 Curable Resin -- 94.9 -- 0.1 -- -- -- --
-- -- 5.0 -- -- -- -- -- 0.1 390 1.0 92 0.0 0.7 Composition 7
Curable Resin 45 45 -- 5.0 -- -- -- -- -- -- 5.0 -- -- -- -- -- 5.3
390 1.0 92 0.0 1.0 Composition 8 Curable Resin 45 45 -- -- 5.0 --
-- -- -- -- 5.0 -- -- -- -- -- 5.3 390 1.0 92 0.1 1.0 Composition 9
Curable Resin 45 45 -- -- -- 5.0 -- -- -- -- 5.0 -- -- -- -- -- 5.3
390 1.0 92 0.0 1.0 Composition 10 Curable Resin 40 40 10 5.0 -- --
-- -- -- -- 5.0 -- -- -- -- -- 5.3 390 1.0 92 0.1 0.9 Composition
11 Curable Resin 45 45 -- -- -- -- 5.0 -- -- -- 5.0 -- -- -- -- --
5.3 390 1.0 92 0.0 1.0 Composition 12 Curable Resin 42.5 42.5 -- 10
-- -- -- -- -- -- 5.0 -- -- -- -- -- 10.5 390 1.0 92 0.0 1.0
Composition 13 Curable Resin 40 40 -- 15 -- -- -- -- -- -- 5.0 --
-- -- -- -- 15.8 390 1.0 92 0.0 1.0 Composition 14 Curable Resin 41
41 -- 4.5 -- -- -- -- -- -- 4.5 9.0 -- -- -- -- 5.2 850 8.0 6.8 0.0
4.2 Composition 15 Curable Resin 41.8 41.8 -- 4.7 -- -- -- -- -- --
4.7 7.0 -- -- -- -- 5.3 850 8.0 12 0.0 4.8 Composition 16 Curable
Resin 47.5 47.5 -- -- -- -- -- -- -- -- 5.0 -- -- -- -- -- 0 390
8.0 92 0.0 7.8 Composition 17 Curable Resin 40 40 -- -- -- -- -- 15
-- -- 5.0 -- -- -- -- -- 0 390 8.0 92 0.0 7.1 Composition 18
Curable Resin 43.3 43.3 -- 8.4 -- -- -- -- -- -- 5.0 -- -- -- -- --
8.8 390 8.0 92 0.0 8.4 Composition 19 Curable Resin -- 94.9 -- 0.1
-- -- -- -- -- -- 5.0 -- -- -- -- -- 0.1 390 8.0 92 0.1 5.2
Composition 20 Curable Resin 45 45 -- 5.0 -- -- -- -- -- -- 5.0 --
-- -- -- -- 5.3 390 8.0 92 0.0 7.9 Composition 21 Curable Resin 45
45 -- -- 5.0 -- -- -- -- -- 5.0 -- -- -- -- -- 5.3 390 8.0 92 0.0
8.0 Composition 22 Curable Resin 45 45 -- -- -- 5.0 -- -- -- -- 5.0
-- -- -- -- -- 5.3 390 8.0 92 0.0 7.9 Composition 23 Curable Resin
40 40 10 5.0 -- -- -- -- -- -- 5.0 -- -- -- -- -- 5.3 390 8.0 92
0.1 7.6 Composition 24 Curable Resin 45 45 -- -- -- -- 5.0 -- -- --
5.0 -- -- -- -- -- 5.3 390 8.0 92 0.0 7.8 Composition 25 Curable
Resin 42.5 42.5 -- 10 -- -- -- -- -- -- 5.0 -- -- -- -- -- 10.5 390
8.0 92 0.1 7.8 Composition 26 Curable Resin 40 40 -- 15 -- -- -- --
-- -- 5.0 -- -- -- -- -- 15.8 390 8.0 92 0.0 7.9 Composition 27
Curable Resin -- 100 -- 0.5 -- -- -- -- -- -- 3.0 -- -- 0.2 -- --
0.5 390 8.0 92 0.0 1.4 Composition 28 Curable Resin -- 100 -- 0.5
-- -- -- -- -- -- 3.0 -- -- -- 0.2 -- 0.5 390 8.0 92 0.0 1.4
Composition 29 Curable Resin -- 100 -- 0.5 -- -- -- -- -- -- 3.0 --
-- -- -- 0.2 0.5 390 8.0 92 0.0 1.4 Composition 30 Curable Resin --
100 -- 0.5 -- -- -- -- -- -- 3.0 -- -- 0.2 -- -- 0.5 390 8.0 92 0.1
5.1 Composition 31 Curable Resin -- 100 -- 0.5 -- -- -- -- -- --
3.0 -- -- -- 0.2 -- 0.5 390 8.0 92 0.1 5.1 Composition 32 Curable
Resin -- 100 -- 0.5 -- -- -- -- -- -- 3.0 -- -- -- -- 0.2 0.5 390
8.0 92 0.1 5.1 Composition 33 Curable Resin -- 100 -- 0.5 -- -- --
-- -- -- 3.0 -- 11 -- -- 0.2 0.5 850 8.0 6.8 0.1 4.4 Composition
34
TABLE-US-00007 TABLE 2 Evaluation Configuration of Polarizing
Polarizer Light Type of Plate Protective WET Resistance Curable
Polarizer Polarizer Film Resin Layer Durability (Xe Resin
Protective Thickness Resin Maximum [B]/ Pencil (60.degree. C.
Irradiation Composition Film (.mu.m) Layer Transmittance ([A] +
[B]) Adhesiveness Hardness 90% 42 d) 15 d) Comparative 1 4 Film 28
25 Curing 6.8% 0 100/100 --(3H) -- -- Example Layer 4 -- -- 2 1
Film 28 25 Curing 6.8% 0 0/100 C(H) Layer 1 3 2 Film 28 25 Curing
6.8% 0 100/100 B(2H) -- -- Layer 2 4 3 Film 28 25 Curing 6.8% 0
100/100 A(3H) -- -- Layer 3 5 5 Film 28 25 Curing 6.8% 0 100/100
C(H) -- -- Layer 5 Example 1 6 Film 28 25 Curing 6.8% 8.8 0/100
A(3H) A A Layer 6 2 7 Film 28 25 Curing 6.8% 0.1 0/100 A(3H) A A
Layer 7 3 8 Film 28 25 Curing 6.8% 5.3 0/100 A(3H) A A Layer 8 4 9
Film 28 25 Curing 6.8% 5.3 0/100 A(3H) A A Layer 9 5 10 Film 28 25
Curing 6.8% 5.3 0/100 A(3H) A A Layer 10 6 11 Film 28 25 Curing
6.8% 5.3 0/100 A(3H) A A Layer 11 7 12 Film 28 25 Curing 6.8% 5.3
4/100 A(3H) A A Layer 12 8 13 Film 28 25 Curing 6.8% 10.5 0/100
B(2H) B A Layer 13 9 14 Film 28 25 Curing 6.8% 15.8 0/100 B(2H) C A
Layer 14 10 8 Film 28 8 Curing 6.8% 5.3 0/100 A(3H) A A Layer 8 11
7 Film 29 25 Curing 6.9% 0.1 0/100 A(3H) A A Layer 7 12 7 Film 29 8
Curing 6.9% 0.1 0/100 A(3H) A A Layer 7 36 28 Film 29 8 Curing 6.9%
0.5 0/100 A(3H) A A Layer 28 37 29 Film 28 8 Curing 6.8% 0.5 0/100
A(3H) A A Layer 29 38 30 Film 28 8 Curing 6.8% 0.5 0/100 A(3H) A A
Layer 30
[0195] The following various evaluations were performed by using
the polarizing plates obtained in the examples and the comparative
examples shown in Table 2. The results are collectively shown in
Table 2.
[0196] (Adhesiveness)
[0197] The surface of the polarizing plate of each of the examples
and comparative examples on a side opposite to the surface on which
the resin layer was formed was bonded to a glass substrate through
an adhesive agent having a thickness of approximately 20 .mu.m, and
thus, a sample was prepared, and the sample was left to stand under
conditions of 25.degree. C. and 60% RH for 2 days, and then, the
surface of the resin layer in the polarizing plate was subjected to
a crosscut peeling test based on JIS K 5400, and evaluation was
performed by the number of peelings. Here, a peeling operation
using tape was continuously performed with respect to the same
sample two times, the total number of peeling of two peeling
operations (the number of peelings after second peeling operation)
was evaluated. Further, continuously performing the peeling
operation two times indicates that the tape is bonded to and peeled
off the sample, and then, the tape is further bonded to and peeled
off from the same sample.
[0198] (Pencil Hardness)
[0199] Pencil hardness of the polarizing plate of each of the
examples and comparative examples was obtained by a test method
based on JIS K 5400(1990) using pencils having different hardness,
and thus, relative evaluation was performed with respect to the
result of the polarizing plate of Comparative Example 1. Evaluation
criteria are as follows. In practice, A or B is preferable.
Further, the pencil hardness was evaluated from a side on which the
resin layer was arranged.
[0200] A: The hardness is identical to or greater than the hardness
of Comparative Example 1.
[0201] B: The hardness is less than the hardness of Comparative
Example 1 by one rank.
[0202] C: The hardness is less than the hardness of Comparative
Example 1 by two ranks.
[0203] Further, in Table 2, in each of the sections, the results of
specific hardness are shown in parentheses along with evaluation of
A to C described above. For example, "(A(3H))" indicates that the
evaluation is A and the specific hardness is 3H.
[0204] (WET Durability)
[0205] The resin layer in the polarizing plate of each of the
examples and the comparative examples was bonded to a glass
substrate through an adhesive agent, a sample was prepared, and the
sample was left to stand under conditions of 60.degree. C. and 90%
RH for 42 days, and then, the degree of polarization of the
polarizing plate was measured by using VAP-7070 (manufactured by
JASCO CORPORATION). Further, the degree of polarization described
above was measured three times, and the average value thereof was
set to the degree of polarization of each of the polarizing
plates.
[0206] In addition, a decreasing rate was obtained from the degree
of polarization by the following expression using the polarizing
plate of Comparative Example 1 as a comparative polarizing plate,
and WET durability was evaluated on the basis of the following
evaluation criteria. In practice, A or B is preferable.
Decreasing Rate (%)=Degree of Polarization (%) of Comparative
Polarizing Plate after Durability Test-Degree of Polarization (%)
of Polarizing Plate of Each Example (or Each Comparative Example)
after Durability Test
[0207] A: The decreasing rate is less than 0.02%.
[0208] B: The decreasing rate is greater than or equal to 0.02% and
less than 0.05%.
[0209] C: The decreasing rate is greater than or equal to
0.05%.
[0210] (Light Resistance)
[0211] The resin layer of the polarizing plate of each of the
examples and comparative examples was bonded to a glass substrate
through an adhesive agent, a sample was prepared, and irradiation
(150 W/cm.sup.2, a super xenon weather meter SX75 (manufactured by
Suga Test Instruments Co., Ltd.)) was performed from the polarizer
protective film side of the sample for 15 days by using a xenon
lamp, and then, the degree of polarization of the polarizing plate
was measured by using VAP-7070 (manufactured by JASCO
CORPORATION).
[0212] In addition, a decreasing rate was obtained from the degree
of polarization by the following expression using the polarizing
plate of Comparative Example 1 as a comparative polarizing plate,
and light resistance was evaluated on the basis of the following
evaluation criteria. In practice, A or B is preferable.
Decreasing Rate (%)=Degree Of Polarization (%) of Comparative
Polarizing Plate after Light Resistance Test-Degree Of Polarization
(%) of Polarizing Plate of Each Example (or Each Comparative
Example) after Light Resistance Test
[0213] A: The decreasing rate is less than 0.02%.
[0214] B: The decreasing rate is greater than or equal to 0.02% and
less than 0.05%.
[0215] C: The decreasing rate is greater than or equal to
0.05%.
[0216] As shown in Table 2, the polarizing plate of the present
invention exhibited excellent pencil hardness and excellent
adhesiveness. In particular, in a case where the mass ratio of the
boronic acid monomer (the mass of the boronic acid monomer/(the
total mass of the boronic acid monomer and the multifunctional
monomer)) is 0.005 mass % to 11.0 mass %, it was confirmed that the
WET durability became more excellent.
[0217] In contrast, in the comparative examples not containing the
boronic acid monomer, adhesiveness deteriorated.
Comparative Example 6
[0218] A curable resin composition 17 shown in Table 1 was applied
onto a separately prepared polarizer (a polarizer containing a
polyvinyl alcohol resin) having a film thickness of 25 .mu.m in
conditions of a transport speed of 24 m/minute by a die coating
method using a slot die disclosed in Example 1 of JP2006-122889A,
and was dried at 60.degree. C. for 60 seconds. After that, a
coating layer was cured by being irradiated with an ultraviolet ray
having illuminance of 400 mW/cm.sup.2 and irradiation dose of 390
mJ/cm.sup.2 under nitrogen purge (an oxygen concentration of
approximately 0.1%) by using an air-cooled metal halide lamp
(manufactured by EYE GRAPHICS Co., Ltd.) of 160 W/cm, and was
wound. The coating amount was adjusted such that the film thickness
of the curing layer became 8 .mu.m. Thus, a curing layer 17 was
prepared on the polarizer.
[0219] Next, the curable resin composition 4 shown in Table 1 was
applied onto the surface of the polarizer on a side opposite to the
surface on which the curing layer 17 was disposed in conditions of
a transport speed of 24 m/minute, and was dried at 60.degree. C.
for 60 seconds. After that, a coating layer was cured by being
irradiated with an ultraviolet ray having illuminance of 400
mW/cm.sup.2 and irradiation dose of 390 mJ/cm.sup.2 under nitrogen
purge (an oxygen concentration of approximately 0.1%) by using an
air-cooled metal halide lamp (manufactured by EYE GRAPHICS Co.,
Ltd.) of 160 W/cm, and was wound. The coating amount was adjusted
such that the film thickness of the curing layer became 1 .mu.m.
Thus, a polarizing plate of Comparative Example 6 was prepared.
Comparative Example 7 and Examples 13 to 24 and 39 to 42
[0220] As shown in Table 3 described below, polarizing plates of
Comparative Example 7 and Examples 13 to 24 and 39 to 42 were
prepared by the same method as that in Comparative Example 6 except
that the curable resin composition shown in Table 1 described above
was used instead of the curable resin composition 17 and the
curable resin composition 4, and the thickness of the polarizer was
changed.
[0221] Further, the configurations of Examples 13 to 24 and 39 to
42 correspond to that of an embodiment in which the resin layer is
arranged on both surfaces of the polarizer.
[0222] In Table 3, the resin layer arranged on one surface of the
polarizer is described as "First Protective Layer", and the resin
layer arranged on the other surface is described as "Second
Protective Layer".
[0223] Further, in general, in a case where the polarizing plate is
used in the image display device, the first protective layer is
arranged such that the first protective layer is directed towards a
visible side (an outer side).
TABLE-US-00008 TABLE 3 Evaluation Type of Curable Configuration of
Polarizing Plate Light Resin Composition First Protective Second
Protective WET Resistance First Second Layer Polarizer Layer First
Protective Layer Second Protective Layer Durability (Xe Protective
Protective (Outer Thickness (Inner Maximum [B]/ Pencil [B]/ Pencil
(60.degree. C. Irradiation Layer Layer Side) (.mu.m) Side)
Transmittance ([A] + [B]) Adhesiveness Hardness ([A] + [B])
Adhesiveness Hardness 90% 42 d) 15 d) Comparative 6 17 4 Curing 25
Curing 92% 0 100/100 --(5H) 0 100/100 --(5H) -- C Example Layer
Layer 17 4 7 18 5 Curing 25 Curing 92% 0 100/100 C(3H) 0 100/100
C(3H) -- -- Layer Layer 18 5 Example 13 21 6 Curing 25 Curing 92%
5.3 0/100 A(5H) 8.8 0/100 A(5H) A -- Layer Layer 21 6 14 21 7
Curing 25 Curing 92% 5.3 0/100 A(5H) 0.1 3/100 A(5H) A -- Layer
Layer 21 7 15 21 8 Curing 25 Curing 92% 5.3 0/100 A(5H) 5.3 0/100
A(5H) A -- Layer Layer 21 8 16 21 9 Curing 25 Curing 92% 5.3 0/100
A(5H) 5.3 0/100 A(5H) A -- Layer Layer 21 9 17 21 10 Curing 25
Curing 92% 5.3 0/100 A(5H) 5.3 0/100 A(5H) A -- Layer Layer 21 10
18 21 11 Curing 25 Curing 92% 5.3 0/100 A(5H) 5.3 0/100 A(5H) A --
Layer Layer 21 11 19 21 12 Curing 25 Curing 92% 5.3 0/100 A(5H) 5.3
3/100 A(5H) A -- Layer Layer 21 12 20 21 13 Curing 25 Curing 92%
5.3 0/100 A(5H) 10.5 0/100 A(5H) B -- Layer Layer 21 13 21 21 14
Curing 25 Curing 92% 5.3 0/100 A(5H) 15.8 0/100 B(4H) C -- Layer
Layer 21 14 22 15 8 Curing 25 Curing 6.8% 5.2 0/100 A(5H) 5.3 0/100
A(5H) A A Layer Layer 15 8 23 16 8 Curing 25 Curing 12% 5.3 0/100
A(5H) 5.3 0/100 A(5H) A B Layer Layer 16 8 24 16 8 Curing 8 Curing
12% 5.3 0/100 A(5H) 5.3 0/100 A(5H) A B Layer Layer 16 8 39 31 28
Curing 8 Curing 92% 0.5 0/100 A(5H) 0.5 0/100 A(5H) A -- Layer
Layer 31 28 40 32 29 Curing 8 Curing 92% 0.5 0/100 A(5H) 0.5 0/100
A(5H) A -- Layer Layer 32 29 41 33 30 Curing 8 Curing 92% 0.5 0/100
A(5H) 0.5 0/100 A(5H) A -- Layer Layer 33 30 42 34 30 Curing 8
Curing 6.8% 0.5 0/100 A(5H) 0.5 0/100 A(5H) A A Layer Layer 34
30
[0224] Various evaluations were performed by using the polarizing
plates obtained in the examples and the comparative examples shown
in Table 3. The results are collectively shown in Table 3. An
evaluation method is as described above.
[0225] Further, the pencil hardness in the section of "First
Protective Layer" and the section of "Second Protective Layer" was
evaluated from a side on which each of the resin layers was
arranged. In addition, the evaluation was performed by using the
polarizing plate of Comparative Example 6 instead of the polarizing
plate of Comparative Example 1. That is, the evaluation was
performed on the basis of the following determination criteria.
[0226] A: The hardness is identical to or greater than the hardness
of Comparative Example 6.
[0227] B: The hardness is less than the hardness of Comparative
Example 6 by one rank.
[0228] C: The hardness is less than the hardness of Comparative
Example 6 by two ranks.
[0229] Further, the determination described above was performed by
being divided into the first protective layer side and the second
protective layer side. That is, the first protective layer of each
of the examples was compared to the curing layer 17 of Comparative
Example 6, and the second protective layer of each of the examples
was compared to a curing layer 4 of Comparative Example 6.
[0230] In addition, in the evaluation of (WET Durability) described
above, the second protective layer in the polarizing plate of each
of the examples and the comparative examples was bonded to a glass
substrate through an adhesive agent, a sample was prepared, and the
sample was used. In addition, the WET durability of Table 3 was
evaluated by using the polarizing plate of Comparative Example 6 as
a comparative polarizing plate instead of the polarizing plate of
Comparative Example 1.
[0231] Further, in the evaluation of (Light Resistance) described
above, the second protective layer in the polarizing plate of each
of the examples and the comparative examples was bonded to the
glass substrate through an adhesive agent, a sample was prepared,
and irradiation was performed from the first protective layer side
of the sample by using a xenon lamp. Further, the light resistance
of Table 3 was evaluated by using the polarizing plate of
Comparative Example 1 as a comparative polarizing plate, as with
Table 2.
[0232] As shown in Table 3, the polarizing plate of the present
invention exhibited excellent pencil hardness and excellent
adhesiveness.
[0233] In contrast, in the comparative examples not containing the
boronic acid monomer, adhesiveness deteriorated.
Comparative Example 8
[0234] A curable resin composition 17 shown in Table 1 was applied
onto a separately prepared polarizer (a polarizer containing a
polyvinyl alcohol resin) having a film thickness of 25 .mu.m in
conditions of a transport speed of 24 m/minute by a die coating
method using a slot die disclosed in Example 1 of JP2006-122889A,
and was dried at 60.degree. C. for 60 seconds. After that, a
coating layer was cured by being irradiated with an ultraviolet ray
having illuminance of 400 mW/cm.sup.2 and irradiation dose of 390
mJ/cm.sup.2 under nitrogen purge (an oxygen concentration of
approximately 0.1%) by using an air-cooled metal halide lamp
(manufactured by EYE GRAPHICS Co., Ltd.) of 160 W/cm, and was
wound. The coating amount was adjusted such that the film thickness
of the curing layer became 8 .mu.m. Thus, a polarizing plate of
Comparative Example 8 was prepared.
[0235] <Polarizing Plates of Comparative Example 9 and Example
25 to 35 and 43 to 46>
[0236] As shown in Table 4 described below, polarizing plates of
Comparative Example 9 and Examples 25 to 35 and 43 to 46 were
prepared by the same method as that in Comparative Example 8 except
that a curable resin composition disclosed in Table 1 described
above was used instead of the curable resin composition 17 and the
thickness of the polarizer was changed.
[0237] Further, the configurations of Examples 25 to 35 and 43 to
46 correspond to the configuration illustrated in FIG. 1.
TABLE-US-00009 TABLE 4 Evaluation Configuration of Light Type of
Polarizing Plate WET Resistance Curable Polarizer Resin Layer
Durability (Xe Resin Thickness Maximum [B]/ Pencil 60.degree. C.
Irradiation Composition Resin Layer (.mu.m) Transmittance ([A] +
[B]) Adhesiveness Hardness 90% 42 d) 15 d) Comparative 8 17 Curing
25 92% 0 100/100 --(5H) -- C Example Layer 17 9 18 Curing 25 92% 0
100/100 C(3H) -- -- Layer 18 Example 25 19 Curing 25 92% 8.8 0/100
A(5H) A -- Layer 19 26 20 Curing 25 92% 0.1 2/100 A(5H) A -- Layer
20 27 21 Curing 25 92% 5.3 0/100 A(5H) A -- Layer 21 28 22 Curing
25 92% 5.3 0/100 A(5H) A -- Layer 22 29 23 Curing 25 92% 5.3 0/100
A(5H) A -- Layer 23 30 24 Curing 25 92% 5.3 0/100 A(5H) A -- Layer
24 31 25 Curing 25 92% 5.3 1/100 A(5H) A -- Layer 25 32 26 Curing
25 92% 10.5 0/100 B(4H) B -- Layer 26 33 27 Curing 25 92% 15.8
0/100 B(4H) C -- Layer 27 34 16 Curing 25 12% 5.3 0/100 A(5H) A B
Layer 16 35 16 Curing 8 12% 5.3 0/100 A(5H) A B Layer 16 43 31
Curing 8 92% 0.5 0/100 A(5H) A -- Layer 31 44 32 Curing 8 92% 0.5
0/100 A(5H) A -- Layer 32 45 33 Curing 8 92% 0.5 0/100 A(5H) A --
Layer 33 46 34 Curing 8 6.8% 0.5 0/100 A(5H) A A Layer 34
[0238] Various evaluations were performed by using the polarizing
plates obtained in the examples and the comparative examples shown
in Table 4. The results are collectively shown in Table 4. An
evaluation method is as described above.
[0239] Further, the pencil hardness in the section of "Resin Layer"
was evaluated from a side on which the resin layer was arranged. In
addition, the evaluation was performed by using the polarizing
plate of Comparative Example 8 instead of the polarizing plate of
Comparative Example 1. That is, the evaluation was performed on the
basis of the following determination criteria.
[0240] A: The hardness is identical to or greater than the hardness
of Comparative Example 8.
[0241] B: The hardness is less than the hardness of Comparative
Example 8 by one rank.
[0242] C: The hardness is less than the hardness of Comparative
Example 8 by two ranks.
[0243] In addition, in the evaluation of (WET Durability), the
polarizer in the polarizing plate of each of the examples and the
comparative examples was bonded to a glass substrate through an
adhesive agent, a sample was prepared, and the sample was used. In
addition, the WET durability of Table 4 was evaluated by using the
polarizing plate of Comparative Example 8 as a comparative
polarizing plate instead of the polarizing plate of Comparative
Example 1.
[0244] Further, in the evaluation of (Light Resistance) described
above, the polarizer in the polarizing plate each of the examples
and the comparative examples was bonded to a glass substrate
through an adhesive agent, a sample was prepared, and irradiation
was performed from the resin layer side of the sample by using a
xenon lamp. Further, the light resistance in Table 4 was evaluated
by using the polarizing plate of Comparative Example 1 as a
comparative polarizing plate, as with Table 2.
[0245] As shown in Table 4, the polarizing plate of the present
invention exhibited excellent pencil hardness and excellent
adhesiveness.
[0246] In contrast, in the comparative examples not containing the
boronic acid monomer, adhesiveness deteriorated.
EXPLANATION OF REFERENCES
[0247] 10,100: polarizing plate [0248] 12: polarizer [0249] 14:
resin layer [0250] 16: polarizer protective film
* * * * *